N.c. automatic folding machine

ABSTRACT

An N.C. automatic folding machine provides programmed positioning of the workpiece, multiple folding, and removal of the workpiece upon completion of the folds. Movement of the workpiece is assisted by a cushion of air. Apparatus and a method of automatically folding and handling sheet material from point of storage to point of ejection of the folded object. A folding die and punch assembly includes a folding die that clamps the workpiece against a supporting surface and a pivotally mounted folding punch that bends the workpiece around the folding die. The folding die is retracted laterally of the supporting surface to strip the workpiece from the die.

[ June ll, 1974 provides procompletion of pieceis assisted by a method of automatipoint of bject. A

3,514,991 6/1970 Merrill et 3,581,535 6/1971 Hinks et al....... 3,618,349 11/1971 Primary ExaminrCharles W. Lanham Assistant ExaminerM. J. Keenan [57] ABSTRACT An N.C. automatic folding machine I grammed positioning of the workpiece, multiple folding, and removal of the workpiece upon the folds. Movement of the work cushion of air. Apparatus and a cally folding and handling sheet material from storage to point of ejection of the folded o folding die and punch assembly includes a folding die that clamps the workpiece against a supporting sur- United States Patent [191 Daniels N.C. AUTOMATIC FOLDING MACHINE [75] Inventor: Dennis Daniels, Bellevue, Wash. [73] Assignee: U.S. Amada, Ltd., South Seattle,

Wash.

[22] Filed: Oct. 4', 1971 [21] Appl. No.: 186,062

[52] US. 72/7, 72/320, 72/461 [51] Int. [58] Field of Search......... ,321, 322, 72/420, 461

[56] References Cited UNITED STATES PATENTS g b i ad e m mc a hen. m u P .m .m o mm mw do C e t 1 nv.l mh o mm m. WwWm m mm a f O t .v a wm m .ld.l m n d c m m w w we e cmmfwm Fader, Berticev Hansen Barrett.. 4. Wilson 22 Claims, 7 Drawing Figures PATENTEBJHN 1 1 m4 sum 2 or 3 O O O O O ooolzo FIG, 3

1 N.'C. AUTOMATIC FOLDING MACHINE BACKGROUND OF THE INVENTION workpiece manually for the next fold. Folding ma-- chines have also heretofore required complicated mechanisms for stripping the workpiece from the folding die such as the use of a gate or some other opening in the sidewall of the machine to pull or slide the work off the folding die. Still-further no system for automatically delivering, folding, and removing the folded object has been used heretofore all previous systems employing extensive use of manual labor.

SUMMARY OF THE INVENTION It is an object of this invention to provide a folding machine which operates automaticallyfrom a numerically controlled or other programming device to provide multiple folds in the workpiece without the need for manual measurement or positioning of the workpiece.

It is another object of this invention to provide a preprogrammed automatic numerically controlled folding machine which automatically positions the workpiece and automatically strips the workpiece from the folding die after the completion of the folds.

Another objectis to provide an inexpensive easily maintained folding die and punch assembly.

Another object of this invention is to provide a unique folding die and punch assembly which utilizes complementary clamping and folding forces so that an increase in one provides an increase in the other.

It is another object of this invention to provide a folding die retractable laterally of the workpiece supporting surface to leave the workpiece on the supporting surface as the workpiece is stripped off the folding die.

Still another object is to provide apparatus and a method for automatically delivering an elongated strip of sheet material, cutting it to a predetermined size, transferring the cut material, folding it, and ejecting the folded object. All operations may be controlled automatically by an N.C. program or the like.

These various objects are best accomplished by providing a-supply of sheet material delivered automatically by a roller feed system to a flying shear, and next operations are automatically performed, preferably according to a prearranged N.C. program.

Another broad feature of the invention is the'unique folding die and punch assembly comprising a one-piece integral folding die having a clamping surface for holding the workpiece against the workpiece supporting surface and a folding punch mounted for pivotal movement towards the folding die for bending the workpiece therearound.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric of a folding apparatus employing the principles of the invention.

FIG. 2 is a plan of the folding apparatus shown in FIG. 1.

FIG. 3 is a vertical sectional view taken along the line 3-3 of FIG. 2.

FIG. 4 is a fragmentary vertical sectional view taken along the line 44 of FIG. 2.

FIG. 5 is a fragmentary perspective of a portion of the folding apparatus of FIG. 1.

. FIG. 6 is a fragmentary vertical section taken along the line 6-6 of FIG. 2.

FIG. 7 is a schematic elevation of an automated sheet materialhandling system embodying the principles of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS workpiece supporting surface 18 to clamp a workpiece W against the supporting surface and for lateral movement for stripping the workpiece off the folding die. A folding punch 26 is pivotally mounted between the side frames to move upwardly against the folding die and to a folding apparatus in which the sheet material is given multiple folds and ejected.

The folding apparatus includes a bed mounted on a frame and workpiece supporting means on the bed. A folding die serves to clamp the workpiece against the supporting surface and in conjunction with a folding punch acts as an anvil to bend the workpiece. Adjustable stops initially position the workpiece relative to the folding die and subsequently reposition the workpiece for making additional folds. The workpiece is stripped from the folding die by retracting the die. All

includes a folding surface 27 to bend the workpiece around the die. The operations of the machine are controlled by an N.C. programming device 28 of any conventional design. A basic program from the numerically controlled device 28 is to initially set the stops 22 to position the workpiece on the workpiece supporting surface, then advance the stops to move the workpiece between the folding die 24 and the workpiece supporting surface, clamp the workpiece, pivot the folding punch at each location at which a fold is desired, and

finally move the folding die laterally across the support-' ing surface leaving the workpiece for automatic ejection from the supporting surface.

The adjustable stops 22 ride within the slots 20 and are keyed to a common shaft 29 which is pivoted by a conventional two-position pneumatic actuator 30 to raise the stops above the supporting surface or lower them for removal of the workpiece. The common shaft 29 is journaled in blocks 32 joined to a cross-shaft 33 having a pair of transversely spaced feed nuts. Advancing screws 34 driven by a conventional drive mechanism 36 advance and return the stops through the nuts and cross-shaft 33 along the supporting surface. The supporting surface is perforated as at 37 to receive air from a pressure chamber 38 attached to the underside a replaceable folding edge 42. Each end of the folding 7 die is mounted for reciprocation toward and away from the-supporting surface 18 within enlarged openings 44 in the side frames 12 and 14. The ends are rigidly secured in slides 50 mounted in guide tracks 52 which are fixed to the side frames 12 and 14. As is readily apparent, downward movement of the slides 50 will draw the folding die toward the supporting surface 18 to clamp the workpiece in a desired position. Upward movement of the slides will release the workpiece so that it may be repositioned.

The folding punch 26 is pivotally mounted between the side frames 12 and 14. For this purpose each end of the punch is provided with an outer ring segment 56 and an inner shaft segment 57. The shaft and ring segments glide in corresponding .inner and outer annular recesses 58 and 59 formed in bronze bearing plates 60 that are secured to the side frames 12 and 14. The inner and outer annular recesses on the bearing plates are concentric to a pivot axis A located adjacent the forward edge of the folding edge 42. As is thus readily apparent, an upward force on the folding punch will pivot the punch about the folding edge 42 and the weight of the punch when the upward force is removed will allow it to return to its lower position shown in FIG. 3. In the lower position the folding surface 27 is in the same plane as the workpiece supporting surface 18 and thus forms an extension thereof. As will be described in more detailbelow, this extension of the workpiece supporting surface uniquely serves to assist in automatically delivering a piece of sheet material to the work piece supporting surface in a completely automated folding system.

The means for lowering the folding die 24 to clamp the workpiece against the workpiece supporting surface 18 and the means to pivot the folding punch 26 upwardly to bend the workpiece are in the preferred'em-' having a piston rod 65. The free end of each rod 65 is secured to a chain 68 which is entrained about a sprocket 70 pivotally secured to a side frame. The chain is fixed at its free end to the folding punch 26. Thus, simultaneous retraction of the two'piston rods 65 on each side of the folding punch 26will first draw tight the chains 68, next move the slides 50 downwardly to move the folding die 24 tightly against the workpiece W, and finally continued retraction of the piston rods 65 will cause the folding punch to pivot about the axis A and'bend the workpiece. Extension of the piston rod 65 will relieve the tension in the chain 68 so that the folding punch will drop to its position shown in FIG. 3. Further extension of the piston rods will bring their free ends into abutment with stop plates 72 so that the brackets 62 will be moved upwardly, thus moving the slides and the folding die away from the workpiece supporting surface.

As mentioned earlier, a unique feature of this invention is that the folding die 24 may be retracted laterally of the workpiece supporting surface 18 to stripthe workpiece off the die. For this purpose a rigid rectangular housing 78 is welded or otherwise fixed to the slide 50 on the side frame 12 of the machine. The housing mounts an inner bearing set of five conventional roller or needle bearings 79 (FIG. 2) and an identical outer set of five roller or needle bearings 80 (FIG. 6). The bearings ride on bearing plates 82 seated in grooves 84 of the folding die 24. The two sets of bearings cantilever the folding die 24 over the workpiece supporting surface as it is moved laterally. In order to position and support the folding die in the opposite side frame 14 the folding die is provided with a bulletshaped pin 86 having a pair of diametrically opposed locating fins 87. The pin and fins fit within a corresponding bore 88 in the slide 50. The bore 88 is provided with diametrically opposed slots 90 to seat the fins. The pin extends further than the fins so that as the folding die approaches the side frame 14 the tapered nose of the pin 86 will first engage the recess 88 centering the folding die in the recess 88 and finally guide the fins 87 into the diametrically opposed slot 90 to accurately position the end of the folding die in the slide 50. The folding die is moved laterally by a conventional electric or pneumatic motor .92 that drives a gear 94.

The gear 94 meshes with a gear track 96 running along the length of the folding die so that rotation of the gear 94 will reciprocate the folding die in the rigid housing 78. As is, of course, obvious control of the motor 92 may also be obtained through the NC. device 28 so that retraction of the folding die may also be preprogrammed and completely automated.

It is by now apparent that the entire operation of the foldingmachine may be carried out completely automatically by the NC. device 28. This automated folding machine can therefore be used in a completely automated delivery system so that a conventional coil or other container of sheet material can be connected through various automated pieces of equipment to enable a completely automated folding method from delivery of material in bulk to the removal of the folded workpiece. A typical apparatus is illustrated in FIG. 7. Sheet material delivered in a coil is supported for free rotation in a conventional cradle 100. The free end of the coil will be fed between straightening and feed rollers 102 of a conventional design. The straightened sheet material leaving the feed rollers will pass across a conventional flying shear 103 where it is cut to the desired size. The material will then be delivered to a transfer table 104. The transfer includes a tiltable top 106 that is movable between the horizontal position where it is aligned with the flying shear 103 to an angular position as shown in FIG. 7 where it is aligned with the folding .surface 27 of the folding punch and the work supporting surface 18 of the folding machine. The table 106 also includes an air receptable and a perforated top so that the table will have a layer or cushion of air for freely sliding the sheet material thereover. Finally a conveyor 107 is provided at the lower end of the workpiece supporting surface so that the completed workpiece when stripped from the folding die can be carried away for subsequent forming operations.

In operation the sheet material will be fed through the feeding and straightening rollers 102 and from there on will be automatically controlled. Each of the units of the system, namely, the straightening and feeding rollers 102, the flying shear 103, transfer table 104, the folding machine, and conveyor 107 all are controlled automatically by the N.C. device. Thus, once the program has been established to determine the size of the workpiece and folding requirements the feeding roller will be suitably energized to advance a prescribed length. The cut material will then be pushed from the flying shear onto the transfer table 104 by the next oncoming piece of sheet material or other suitable means. The sliding will be facilitated on the top of the transfer tableby the cushion of air. Next the top 106 will be raised so that the workpiece W is free to slide off the top onto the workpiece supporting surface of the folding machine. During transfer of the workpiece it is initially guided by the folding surface 27 of the folding punch 26. When the workpiece hits the stops 22, which have been preset to initiate the folding operation, the workpiece will come to rest. Next the folds will be made in the workpiece and when the last fold is made, the folding die will be stripped from the workpiece. The cushion of air on the workpiece supporting surface will allow the workpiece to then slide down onto the conveyor 107.

While the preferred form of the invention has been illustrated and described, it should be understood that modifications will be readily apparent to one skilled in the art. Accordingly, the invention is not to be limited to the specific forms illustrated and described, but rather is to be limited solely by a literal interpretation of the claims appended hereto. For example, although the invention has been described for use with a preprogrammed control, it is obviously equally advantageously used with manually operated controls.

What is claimed is: 1. An automatic or programmable folding machine for sheet'metal material or the like workpieces each having side and end surfaces, comprising;

workpiece supporting means on said base frame, powered workpiece stop means continuously engaging during advancing and folding an-end surface of said workpiece and movable to initially position the workpiece end surface on the workpiece supporting means and subsequently advance the workpiece end surface after each fold so that the location of each fold on the workpiece is determined by the position of the end surface engaging stop means, means for clamping the workpiece on the supporting means for holding the workpiece during folding,

anvil means for defining an edge about whichthe workpiece is folded, said edge facing away from said stop means and toward an unrestricted opening through which a folding punch can pass, said anvil means having a relatively short forward surface adjacent said anvil edge and having a top surface and a rear surface of relatively short dimensions for allowing the workpiece to be bent around on itself rearwardly of said rear surface,

a powered folding punch for forming the workpiece over the anvil means, means for removing the workpiece from said anvil means, and

wherein said powered stop means, clamping means. folding punch and workpiece removing means can be actuated to make multiple folds in the workpiece automatically.

2. The machine of claim 1, including means for automatically ejecting the workpiece fromsaid workpiece supporting means.

3. The machine of claim 1, said folding punch being mounted for pivotal movement, said means for pivotally mounting said folding punch comprising bearing plates secured to each said side frame, said bearing plates each including an annular outer recess spaced from the pivot axis of said folding punch and an inner recess spaced between the pivot axis and said outer recess, said inner and outer recesses being concentric with said pivot axis, and said folding punch including an outer ring segment and an inner shaft segment extending laterally of each end of said folding punch and slid ably received in said inner and outer recesses respectively.

4. The machine of claim 1, said workpiece supporting means including means for providing a layer of air along the top thereof for reducing the friction beneath the workpiece and the workpiece supporting means.

5. The machine of claim 2, said workpiece supporting means being at an angle with respect to the horizontal and said workpiece ejecting means including means for providing a layer of air along the top of said workpiece supporting means to reduce the friction between the workpiece and the supporting means, and means for lowering said adjustable stop means beneath the supporting means for permitting the workpiece to slide freely off the supporting means.

6. The machine of claim 1, including means for holding a roll of sheet material, means for straightening the material, means for automatically cutting the material into sheets of predetermined size, and means for automatically transferring the cut material to said workpiece supporting surface and against said adjustable stops.

7. The method of automatically forming sheet material objects comprising moving an elongated strip of sheet material along a path, straightening the material as it travels in said path, automatically cutting the material into lengths with forward and rearward end edges in accordance with a prearranged numerically controlled program, moving the cut material out of said path and onto a material folding surface automatically folding the material at a first location on the material measured a first distance from the rearward end edge of the material in accordance with said prearranged numerically controlled program, automatically moving the material along the material folding surface and folding the material to provide additional folds at locations again measured from the rearward end edge of the material in accordance with said prearranged numerically controlled program, said steps of automatically folding and advancing including continuously engaging the rearward end edge of the cut length of sheet material during advancing and folding through a series of folding steps, and automatically moving the folded material off the material folding surface.

8. An automatic folding machine for sheet metal material or the like comprising; a base frame, workpiece supporting means on said base frame, adjustable stop means automatically positionable for initially positioning the workpiece on the supporting means and advancing it in predetermined increments, means for automatically clamping the'workpiece on the supporting means for-holding the workpiece during the folding, anvil means for defining an edge about which the workpiece is folded, a folding punch automatically actuated for forming the workpiece over the anvil means, means for removing the workpiece from said anvil means, and wherein said adjustable stop means, clamping means, folding punch and workpiece removing means are automatically actuated whereby multiple folds are made in the workpiece automatically, said means for clamping the workpiece and said anvil means being combined as an integral folding die mounted for movement toward and away from said workpiece supporting means, said folding punch and said means for clamping the workpiece being operatively interconnected for clamping the workpiece against theworkpiece supporting means'with the same force transmitting means employed to actuate the folding punch for forming the workpiece so that an increase in folding force results in an increase in clamping force, said base frame including transversely spaced side frames, said means for moving said folding die. toward and away from said workpiece supporting means including a guideway on each side frame and a slide reciprocably mounted in each guideway, said slides being secured to opposite ends of said folding die, said workpiece removing means including means for retracting said folding die laterally of the workpiece supporting means whereby the folding die is stripped off the workpiece leaving the workpiece on the supporting means.

9. An automatic folding machine for sheet metal material or the like comprising; a base frame, workpiece supporting means on said base frame, adjustable stop means automatically positionable for initially positioning the workpiece on the supporting means and advancing it in predetermined increments, means for automatically clamping the workpiece on the supporting means for holding the workpiece during the folding,

, anvil means for defining an edge about which the workthe workpiece being operatively interconnected for clamping the workpiece against the workpiece supporting means with the same force transmitting means employed to actuate the folding punch for forming the workpiece so that an increase in folding force results in an increase in clamping force, said base frame including transversely spaced side frames, said means for moving said folding die toward and away from said workpiece supporting means including a guideway on each side frame and a slide reciprocably mounted in each guideway, said slides being secured to opposite ends of said folding die, and said folding die moving 'means for' clamping the workpiece including ram means mounted on brackets secured to each of said slides, each ram means having a piston rod secured at its free end to a chain, said chains being secured at their free ends to the opposite ends of said folding punch, said folding punch being mounted for pivotal movement into engagement with said folding die whereby retraction of said piston rods first effects movement of said folding die toward said workpiece supporting means to clamp the workpiece and subsequently pivots said folding punch toward said folding die to form the workpiece on the anvil of said folding die.

10. The machine of claim 9, said means for pivotally mounting said folding punch comprising bearing plates secured to each said side frame, said bearing plates each including an annular outer recess spaced from the pivot axis of said folding punch and an inner recess spaced between the pivot axis and said outer recess, said inner and outer recesses being concentric with said pivot axis, and said folding punch including an outer ring segment and an inner shaft segment extending laterally of each end of said folding punch and slidably received in said inner and outer recesses respectively.

11. A folding mechanism for a folding machine having a support frame with a workpiece supporting surface, the improvement comprising a one-piece integral folding die having a clamping surface for holding the workpiece against the supporting surface and a folding anvil, a folding punch mounted for pivotal movement toward the'folding anvil for bending the workpiece around the folding anvil, means for moving said folding die toward said supporting surface toclamp the workpiece therebetween, means for pivoting the folding punch toward and away from said folding anvil, and means for removing the workpiece from said folding die, said workpiece removing means including means for moving said folding die laterally of said workpiece supporting surface, and means for stripping the workpiece from the folding die as it is moved laterally,

12. The folding mechanism of claim 11, one of said slides including a bearing housing having two sets of bearings for supporting the folding die as it is moved laterally, the opposite end of said folding die including a tapered pin having diametrical keys, the slide adjacent said tapered pin having an opening and diametrical keyways for receiving said pin and keys wherein the folding die is supported by the slides during a folding operation.

13. The apparatus of claim 11 said anvil having a relatively short forward surface adjacent said edge and having a top surface and a rear surface of relatively short dimensions for allowing the workpiece to be bent around on itself rearwardly of said rear surface.

folding die having a clamping surface for holding the workpiece against the supporting surface and a folding anvil for bending the workpiece around the folding'anvil, means for moving said folding die toward said supporting surface to clamp the workpiece therebetween,

means for pivoting the folding punch toward and away from said folding anvil, and means for removing the workpiece from said folding die including spaced side frames secured to said support frame, said means for moving the folding die toward the workpiece supporting surface and said means for pivoting the folding punch including guideways on said side frames, slides in said guideways movable toward and away from said workpiece supporting surface, ram means secured to said slides and each having a piston rod extendable therefrom, chains secured to said piston rods and to the ends of said folding punch wherein retraction of said piston rods draws said folding die toward the supporting surface to clamp the workpiece and subsequently pivots the folding punch toward said folding anvil to form the workpiece.

15. The folding mechanism of claim 14, said side frames including bearing plates each having an annular outer recess spaced from the pivot axis of said folding punch and an inner recess spaced between the pivot axis and said annular outer recess, said inner and outer recesses being concentric with said pivot axis of said folding punch, and said folding punch including an outer ring segment and an inner shaft segment extending laterally of each end of said folding punch and slidably received in said inner and outer recesses, respectively, a bearing housing rigidly secured to one of said slides and including two sets of spaced bearings for supporting the folding die as it is moved laterally, the opposite end of said folding die including a tapered pin provided with a pair of diametrical keys, the slide adjacent said tapered pin having an opening and diametrical keyways for receiving said pin and keys wherein the folding die is supported by the slides during a folding operation.

16; A folding mechanism for a folding machine having a support frame with a workpiece supporting surface, the improvement comprising a one-piece integral folding die having a clamping surface for holding the workpiece against the supporting surface and a folding anvil, a folding punch mounted for pivotal movement toward the folding anvil for bending the workpiece around the folding anvil, means for moving said folding die toward said supporting surface to clamp the workpiece therebetween, means for pivoting the folding punch toward and away from said folding anvil, and means for removing the workpiece from said folding die, said means for moving the folding die toward said supporting surface to clamp the workpiece and said means for pivoting the folding punch being interconnected so that the punch and die are moved interdependently toward one another by a common connection whereby the clamping force on the workpiece is directly related to the folding force applied by the folding punch, said workpiece removing means including means for moving said folding die laterally of the workpiece supporting surface, and means for stripping the workpiece from the folding die as it is moved laterally.

17. An automatic or programmable folding machine for sheet metal material or the like comprising;

a base frame,

workpiece supporting means on said base frame,

powered workpiece stop means positionable for initially positioning the workpiece on the supporting means and advancing it over the supporting means,

means for clamping the workpiece on the supportingmeans for holding the workpiece during folding, anvil means for defining an edge about which the workpiece is folded,

a powered folding punch for forming the workpiece over the anvil means, means coupling the folding punch with the clamping means for increasing the clamping force in response to an increase in folding force applied on the folding punch, means for removing the workpiece from said anvil means, and wherein said powered stop means, clamping means, folding punch and workpiece removing means can be actuated to make multiple folds in the workpiece automatically.

18. The machine of claim 17, said base frame including transversely spaced side frames, said means for clamping the workpiece on the supporting means including a guideway on each said side frame and a slide reciprocably mounted in said each guideway, said slide being secured to opposite end of said anvil means.

19. A folding mechanism for a folding machine having a support frame with a workpiece supporting surface, the improvement comprising a one-piece integral folding die having a folding anvil and a clamping surface for holding the workpiece against the supporting surface, a folding punch mounted for pivotal movement toward the folding anvil for bending the workpiece around the folding anvil, and interconnecting means for pulling the punch and die toward one another whereby the clamping force on the workpiece is increased directly in response to an increase in the folding force applied on the folding punch.

20. An automatic or programmable folding machine for sheet material or the like workpieces each having an end surface comprising a base frame, workpiece supporting means on said base frame, powered workpiece stop means continuously engageable with said end surface during advancing and folding and positionable for initially positioning the workpiece on the supporting means and advancing it over the supporting means after each fold, means for clamping the workpiece on the supporting means for holding the workpiece during the folding operation, anvil means for defining an exposed edge facing away from said stop means about which the workpiece is folded, said anvil means having a relatively short forward surface adjacent said anviledge and having a top surface and a rear surface of relatively short dimensions for allowing the workpiece to be bent around on itself rearwardly of said rear surface, a powered folding punch for forming the workpiece over the anvil means, and wherein said powered stop means, clamping means, folding punch and workpiece removing means can be acutated to make multiple folds in the workpiece automatically. 1

21. An automatic --or programmable folding machine for sheet material or the like workpieces having side and end surfaces, comprising, a base frame, workpiece supporting means on said base frame, powered workpiece stop means positionable for initially positioning the workpiece on the supporting means and advancing the workpiece, said stop means including means for engaging an end surface of the workpiece so that all movements of the workpiece are based on the position of the end surface of the workpiece, means for clamping the workpiece on the supporting means for'holding the workpiece during folding, anvil means for defining an edge about which the workpiece is folded, said edge facing away from said stop means and toward an unrestricted opening through which a folding punch can pass, said anvil means having a relatively short forward surface adjacent said anvil edge and having a top surfaceand a rear surface of relatively short dimensions for allowing the workpiece to be bent around on itself rearwardly of said rear surface, a powered folding punch for formingthe workpiece over the anvil means, means for removing the workpiece from said anvil means, wherein said powered stop means, clamping means, folding punch and workpiece removing means can be actuated to make multiple folds in the workpiece automatically, including means for holding a roll of sheet material, means for straightening the material, means for automatically cutting the material into sheets of predetermined size, and means for automatically transferring the cut material to said workpiece supporting surface and against said means for engaging an end surface of the workpiece, said transferring means including a table having a tiltable top, means for providing a layer of air along the top of the table for reducing the friction between the sheet material and the table, and means for tilting the table into an inclined plane to slide the material off the table, said workpiece supporting means-of said machine lying in said inclined plane, means for providing a layer of air along said supporting means for raising the workpiece off the supporting means to reduce the friction between the workpiece and the supporting means whereby the sheet material is automatically transferred from the transfer table to said supporting surface by sliding along said inclined plane.

22. The method of automatically forming sheet material objects comprising moving an elongated strip of sheet material along a path, straightening the material as it travels in said path, automatically cutting the material into lengths with forward and rearward end edges in accordance with a prearranged numerically controlled program, moving the cut material out of said path and onto a material folding surface, automatically folding the materialat a first location on the material measured a first distance from the rearward end edge of the material in accordance with said prearranged numerically controlled program, automatically moving the material along the material folding surface and folding the material to provide additional folds at locations again measured from the rearward end edge of the material in accordance with said prearranged nu merically controlled program, and automatically mov' ing the folded material off the material folding surface, said step of moving the cut material out of said path and onto said material folding surface including lifting the material into an inclined path, raising the material on a layer of air and sliding it onto an inclined material surface, said step of moving the material along the material folding surface including raising the material on a layer of air and sliding the material up said surface, and said step of moving the folded material off the folding surface including raising the material on a layer of air and sliding the material down said inclined material surface. 

1. An automatic or programmable folding machine for sheet metal material or the like workpieces each having side and end surfaces, comprising; workpiece supporting means on said base frame, powered workpiece stop means continuously engaging during advancing and folding an end surface of said workpiece and movable to initially position the workpiece end surface on the workpiece supporting means and subsequently advance the workpiece end surface after each fold so that the location of each fold on the workpiece is determined by the position of the end surface engaging stop means, means for clamping the workpiece on the supporting means for holding the workpiece during folding, anvil means for defining an edge about which the workpiece is folded, said edge facing away from said stop means and toward an unrestricted opening through which a folding punch can pass, said anvil means having a relatively short forward surface adjacent said anvil edge and having a top surface and a rear surface of relatively short dimensions for allowing the workpiece to be bent around on itself rearwardly of said rear surface, a powered folding punch for forming the workpiece over the anvil means, means for removing the workpiece from said anvil means, and wherein said powered stop means, clamping means, folding punch and workpiece removing means can be actuated to make multiple folds in the workpiece automatically.
 2. The machine of claim 1, including means for automatically ejecting the workpiece from said workpiece supporting means.
 3. The machine of claim 1, said folding punch being mounted for pivotal movement, said means for pivotally mounting said folding punch comprising bearing plates secured to each said side frame, said bearing plates each including an annular outer recess spaced from the pivot axis of said folding punch and an inner recess spaced between the pivot axis and said outer recess, said inner and outer recesses being concentric with said pivot axis, and said folding punch including an outer ring segment and an inner shaft segment extending laterally of each end of said folding punch and slidably received in said inner and outer recesses respectively.
 4. The machine of claim 1, said workpiece supporting means including means for providing a layer of air along the top thereof for reducing the friction beneath the workpiece and the workpiece supporting means.
 5. The machine of claim 2, said workpiece supporting means being at an angle with respect to the horizontal and said workpiece ejecting means including means for providing a layer of air along the top of said workpiece supporting means to reduce the friction between the workpiece and the supporting means, and means for lowering said adjustable stop means beneath the supporting means for permitting the workpiece to slide freely off the supporting means.
 6. The machine of claim 1, including means for holding a roll of sheet material, means for straightening the material, means for automatically cuttiNg the material into sheets of predetermined size, and means for automatically transferring the cut material to said workpiece supporting surface and against said adjustable stops.
 7. The method of automatically forming sheet material objects comprising moving an elongated strip of sheet material along a path, straightening the material as it travels in said path, automatically cutting the material into lengths with forward and rearward end edges in accordance with a prearranged numerically controlled program, moving the cut material out of said path and onto a material folding surface automatically folding the material at a first location on the material measured a first distance from the rearward end edge of the material in accordance with said prearranged numerically controlled program, automatically moving the material along the material folding surface and folding the material to provide additional folds at locations again measured from the rearward end edge of the material in accordance with said prearranged numerically controlled program, said steps of automatically folding and advancing including continuously engaging the rearward end edge of the cut length of sheet material during advancing and folding through a series of folding steps, and automatically moving the folded material off the material folding surface.
 8. An automatic folding machine for sheet metal material or the like comprising; a base frame, workpiece supporting means on said base frame, adjustable stop means automatically positionable for initially positioning the workpiece on the supporting means and advancing it in predetermined increments, means for automatically clamping the workpiece on the supporting means for holding the workpiece during the folding, anvil means for defining an edge about which the workpiece is folded, a folding punch automatically actuated for forming the workpiece over the anvil means, means for removing the workpiece from said anvil means, and wherein said adjustable stop means, clamping means, folding punch and workpiece removing means are automatically actuated whereby multiple folds are made in the workpiece automatically, said means for clamping the workpiece and said anvil means being combined as an integral folding die mounted for movement toward and away from said workpiece supporting means, said folding punch and said means for clamping the workpiece being operatively interconnected for clamping the workpiece against the workpiece supporting means with the same force transmitting means employed to actuate the folding punch for forming the workpiece so that an increase in folding force results in an increase in clamping force, said base frame including transversely spaced side frames, said means for moving said folding die toward and away from said workpiece supporting means including a guideway on each side frame and a slide reciprocably mounted in each guideway, said slides being secured to opposite ends of said folding die, said workpiece removing means including means for retracting said folding die laterally of the workpiece supporting means whereby the folding die is stripped off the workpiece leaving the workpiece on the supporting means.
 9. An automatic folding machine for sheet metal material or the like comprising; a base frame, workpiece supporting means on said base frame, adjustable stop means automatically positionable for initially positioning the workpiece on the supporting means and advancing it in predetermined increments, means for automatically clamping the workpiece on the supporting means for holding the workpiece during the folding, anvil means for defining an edge about which the workpiece is folded, a folding punch automatically actuated for forming the workpiece over the anvil means, means for removing the workpiece from said anvil means, and wherein said adjustable stop means, clamping means, folding punch and workpiece removing means are automatically actuated whereby multiple folds are made in the workpiece automatically, said mEans for clamping the workpiece and said anvil means being combined as an integral folding die mounted for movement toward and away from said workpiece supporting means, said folding punch and said means for clamping the workpiece being operatively interconnected for clamping the workpiece against the workpiece supporting means with the same force transmitting means employed to actuate the folding punch for forming the workpiece so that an increase in folding force results in an increase in clamping force, said base frame including transversely spaced side frames, said means for moving said folding die toward and away from said workpiece supporting means including a guideway on each side frame and a slide reciprocably mounted in each guideway, said slides being secured to opposite ends of said folding die, and said folding die moving means for clamping the workpiece including ram means mounted on brackets secured to each of said slides, each ram means having a piston rod secured at its free end to a chain, said chains being secured at their free ends to the opposite ends of said folding punch, said folding punch being mounted for pivotal movement into engagement with said folding die whereby retraction of said piston rods first effects movement of said folding die toward said workpiece supporting means to clamp the workpiece and subsequently pivots said folding punch toward said folding die to form the workpiece on the anvil of said folding die.
 10. The machine of claim 9, said means for pivotally mounting said folding punch comprising bearing plates secured to each said side frame, said bearing plates each including an annular outer recess spaced from the pivot axis of said folding punch and an inner recess spaced between the pivot axis and said outer recess, said inner and outer recesses being concentric with said pivot axis, and said folding punch including an outer ring segment and an inner shaft segment extending laterally of each end of said folding punch and slidably received in said inner and outer recesses respectively.
 11. A folding mechanism for a folding machine having a support frame with a workpiece supporting surface, the improvement comprising a one-piece integral folding die having a clamping surface for holding the workpiece against the supporting surface and a folding anvil, a folding punch mounted for pivotal movement toward the folding anvil for bending the workpiece around the folding anvil, means for moving said folding die toward said supporting surface to clamp the workpiece therebetween, means for pivoting the folding punch toward and away from said folding anvil, and means for removing the workpiece from said folding die, said workpiece removing means including means for moving said folding die laterally of said workpiece supporting surface, and means for stripping the workpiece from the folding die as it is moved laterally.
 12. The folding mechanism of claim 11, one of said slides including a bearing housing having two sets of bearings for supporting the folding die as it is moved laterally, the opposite end of said folding die including a tapered pin having diametrical keys, the slide adjacent said tapered pin having an opening and diametrical keyways for receiving said pin and keys wherein the folding die is supported by the slides during a folding operation.
 13. The apparatus of claim 11 said anvil having a relatively short forward surface adjacent said edge and having a top surface and a rear surface of relatively short dimensions for allowing the workpiece to be bent around on itself rearwardly of said rear surface.
 14. A folding mechanism for a folding machine having a support frame with a workpiece supporting surface, the improvement comprising a one-piece integral folding die having a clamping surface for holding the workpiece against the supporting surface and a folding anvil for bending the workpiece around the folding anvil, means for moving said folding die toward said supporting surface to clamp the workpiece therebetweEn, means for pivoting the folding punch toward and away from said folding anvil, and means for removing the workpiece from said folding die including spaced side frames secured to said support frame, said means for moving the folding die toward the workpiece supporting surface and said means for pivoting the folding punch including guideways on said side frames, slides in said guideways movable toward and away from said workpiece supporting surface, ram means secured to said slides and each having a piston rod extendable therefrom, chains secured to said piston rods and to the ends of said folding punch wherein retraction of said piston rods draws said folding die toward the supporting surface to clamp the workpiece and subsequently pivots the folding punch toward said folding anvil to form the workpiece.
 15. The folding mechanism of claim 14, said side frames including bearing plates each having an annular outer recess spaced from the pivot axis of said folding punch and an inner recess spaced between the pivot axis and said annular outer recess, said inner and outer recesses being concentric with said pivot axis of said folding punch, and said folding punch including an outer ring segment and an inner shaft segment extending laterally of each end of said folding punch and slidably received in said inner and outer recesses, respectively, a bearing housing rigidly secured to one of said slides and including two sets of spaced bearings for supporting the folding die as it is moved laterally, the opposite end of said folding die including a tapered pin provided with a pair of diametrical keys, the slide adjacent said tapered pin having an opening and diametrical keyways for receiving said pin and keys wherein the folding die is supported by the slides during a folding operation.
 16. A folding mechanism for a folding machine having a support frame with a workpiece supporting surface, the improvement comprising a one-piece integral folding die having a clamping surface for holding the workpiece against the supporting surface and a folding anvil, a folding punch mounted for pivotal movement toward the folding anvil for bending the workpiece around the folding anvil, means for moving said folding die toward said supporting surface to clamp the workpiece therebetween, means for pivoting the folding punch toward and away from said folding anvil, and means for removing the workpiece from said folding die, said means for moving the folding die toward said supporting surface to clamp the workpiece and said means for pivoting the folding punch being interconnected so that the punch and die are moved interdependently toward one another by a common connection whereby the clamping force on the workpiece is directly related to the folding force applied by the folding punch, said workpiece removing means including means for moving said folding die laterally of the workpiece supporting surface, and means for stripping the workpiece from the folding die as it is moved laterally.
 17. An automatic or programmable folding machine for sheet metal material or the like comprising; a base frame, workpiece supporting means on said base frame, powered workpiece stop means positionable for initially positioning the workpiece on the supporting means and advancing it over the supporting means, means for clamping the workpiece on the supporting means for holding the workpiece during folding, anvil means for defining an edge about which the workpiece is folded, a powered folding punch for forming the workpiece over the anvil means, means coupling the folding punch with the clamping means for increasing the clamping force in response to an increase in folding force applied on the folding punch, means for removing the workpiece from said anvil means, and wherein said powered stop means, clamping means, folding punch and workpiece removing means can be actuated to make multiple folds in the workpiece automatically.
 18. The machine of claim 17, said base frame includinG transversely spaced side frames, said means for clamping the workpiece on the supporting means including a guideway on each said side frame and a slide reciprocably mounted in said each guideway, said slide being secured to opposite end of said anvil means.
 19. A folding mechanism for a folding machine having a support frame with a workpiece supporting surface, the improvement comprising a one-piece integral folding die having a folding anvil and a clamping surface for holding the workpiece against the supporting surface, a folding punch mounted for pivotal movement toward the folding anvil for bending the workpiece around the folding anvil, and interconnecting means for pulling the punch and die toward one another whereby the clamping force on the workpiece is increased directly in response to an increase in the folding force applied on the folding punch.
 20. An automatic or programmable folding machine for sheet material or the like workpieces each having an end surface comprising a base frame, workpiece supporting means on said base frame, powered workpiece stop means continuously engageable with said end surface during advancing and folding and positionable for initially positioning the workpiece on the supporting means and advancing it over the supporting means after each fold, means for clamping the workpiece on the supporting means for holding the workpiece during the folding operation, anvil means for defining an exposed edge facing away from said stop means about which the workpiece is folded, said anvil means having a relatively short forward surface adjacent said anvil edge and having a top surface and a rear surface of relatively short dimensions for allowing the workpiece to be bent around on itself rearwardly of said rear surface, a powered folding punch for forming the workpiece over the anvil means, and wherein said powered stop means, clamping means, folding punch and workpiece removing means can be acutated to make multiple folds in the workpiece automatically.
 21. An automatic or programmable folding machine for sheet material or the like workpieces having side and end surfaces, comprising, a base frame, workpiece supporting means on said base frame, powered workpiece stop means positionable for initially positioning the workpiece on the supporting means and advancing the workpiece, said stop means including means for engaging an end surface of the workpiece so that all movements of the workpiece are based on the position of the end surface of the workpiece, means for clamping the workpiece on the supporting means for holding the workpiece during folding, anvil means for defining an edge about which the workpiece is folded, said edge facing away from said stop means and toward an unrestricted opening through which a folding punch can pass, said anvil means having a relatively short forward surface adjacent said anvil edge and having a top surface and a rear surface of relatively short dimensions for allowing the workpiece to be bent around on itself rearwardly of said rear surface, a powered folding punch for forming the workpiece over the anvil means, means for removing the workpiece from said anvil means, wherein said powered stop means, clamping means, folding punch and workpiece removing means can be actuated to make multiple folds in the workpiece automatically, including means for holding a roll of sheet material, means for straightening the material, means for automatically cutting the material into sheets of predetermined size, and means for automatically transferring the cut material to said workpiece supporting surface and against said means for engaging an end surface of the workpiece, said transferring means including a table having a tiltable top, means for providing a layer of air along the top of the table for reducing the friction between the sheet material and the table, and means for tilting the table into an inclined plane to slide the material off the table, said workpiece supporting means of said machine lying in said inclined planE, means for providing a layer of air along said supporting means for raising the workpiece off the supporting means to reduce the friction between the workpiece and the supporting means whereby the sheet material is automatically transferred from the transfer table to said supporting surface by sliding along said inclined plane.
 22. The method of automatically forming sheet material objects comprising moving an elongated strip of sheet material along a path, straightening the material as it travels in said path, automatically cutting the material into lengths with forward and rearward end edges in accordance with a prearranged numerically controlled program, moving the cut material out of said path and onto a material folding surface, automatically folding the material at a first location on the material measured a first distance from the rearward end edge of the material in accordance with said prearranged numerically controlled program, automatically moving the material along the material folding surface and folding the material to provide additional folds at locations again measured from the rearward end edge of the material in accordance with said prearranged numerically controlled program, and automatically moving the folded material off the material folding surface, said step of moving the cut material out of said path and onto said material folding surface including lifting the material into an inclined path, raising the material on a layer of air and sliding it onto an inclined material surface, said step of moving the material along the material folding surface including raising the material on a layer of air and sliding the material up said surface, and said step of moving the folded material off the folding surface including raising the material on a layer of air and sliding the material down said inclined material surface. 